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排序方式: 共有2748条查询结果,搜索用时 124 毫秒
1.
目的观察认知行为干预在冠心病患者护理中的应用效果。方法选取本院2016年12月~2018年2月期间收治的53例冠心病患者,根据住院号奇偶性情况将其随机分为观察组(n=27)和对照组(n=26),对照组予以常规护理,观察组予以认知行为干预。比较两组患者控制态度评分、心理状况评分、生活质量改善情况及依从性。结果观察组控制态度评分、心理状况评分、生活质量改善情况及依从性与对照组比较,差异有统计学意义(P0.05)。结论在冠心病患者护理中给予认知行为干预应用效果极佳,可作为临床干预首选措施。 相似文献
2.
3.
目的了解利培酮治疗儿童少年期首发精神分裂症或分裂样精神病的临床疗效、安全性和药物剂量。方法用利培酮对62例年龄<14岁的儿童精神分裂症患者治疗8周,采用简明精神病评定量表(BPRS)评定疗效,副反应量表(TESS)及实验室相应检查评定安全性及副反应。结果总有效率85%。不良反应主要为锥体外系反应及失眠,平均治疗剂量(3.26±0.88)mg/d。结论利培酮对于首发儿童少年期精神分裂症或分裂样精神病的治疗,用药安全、疗效可靠、副反应小、依从性高。 相似文献
4.
Hitoshi Ogino Nongchana Klangsuk Wu Jin Christopher T. Bowles Magdi H. Yacoub 《Artificial organs》1995,19(6):525-534
Abstract: The dependence of transient pressure characteristics of a ventricular assist device (VAD) on the compliance of its housing and cannulas was investigated in a mock circulation. The peak rate of change of pressure ( dP/dt max ) values was greater in the cannulas than other compartments and was associated with valve closure-induced pressure oscillations. When cannula compliance was increased from 0.0057 to 0.0129 cm3 /mm Hg, these values decreased by ˜20%, and outflow cannula pressure oscillation frequency decreased from 17.5 Hz by 35%. This trend was also apparent in the inflow. A VAD housing compliance increase from 0.0162 to 0.0483 cm3 /mm Hg caused a dP/dt max decrease of 30% in both the blood chamber and the outflow cannula. The effect of this change on the inflow was weaker implying that housing absorbs the energy associated with outflow deceleration more effectively than the inflow. These findings suggest that increasing VAD housing and cannulas compliance can improve hydrodynamic performance. 相似文献
5.
Dan Greitz 《Child's nervous system》2007,23(5):487-489
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively
absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims
to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV)
in communicating hydrocephalus.
Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the
theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve
after ETV.
Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into
the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously
compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement
of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply
by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the
CSF sufficiently. 相似文献
6.
S. E. Greenwald C. E. Collino C. L. Berry 《Medical & biological engineering & computing》1988,26(5):497-502
An in vitro method for obtaining pressure/volume curves from the lungs of small animals is described. The excised lungs were
inflated and deflated with saline or air by a motor-driven syringe controlled by a microcomputer. The computer was programmed
to display the curves in real time, correcting when necessary for the compressibility of air in the system. Volume compliance
(K=dV/dP×1/V) was calculated by differentiating a polynomial fitted to the measured pressure/volume points. Repeatable curves
were obtained from mice aged 24h (body weight 1·3±0·14g (SD), residual lung volume 8·43±1·5 μl (SD). A nonlinear decrease
in differential compliance (K=dV/dP×1/V) with increasing strain was observed while the ratio Ksaline/Kair increased from 2·5 to 10 over the range of strains investigated (ε=1–5). The relative surface tension (calculated from the
difference between the pressures required to inflate the air and saline-filled organs to a given volume) increased exponentially
with increasing volume. We conclude that it is now possible to obtain reproducible pressure/volume curves for lungs with a
residual volume of less than 10 μl, from animals weighing approximately 1·5 g and, from these curves, estimate airway compliance
and surface tension. 相似文献
7.
上海市区居民高血压药物治疗概况的横断面调查 总被引:36,自引:0,他引:36
本文报告上海市区三个中等生活水平居民区中540例35岁以上高皿压患者药物治疗概况。结果显示,高血压患者中有13.O/不知自己有高血压,而已知有高血压者中仅50%规则服用降压药,其中30.8%患者的血压得到控制。54O例高血压患者总的血压控制率仅为20%。导致血压控制率低的原因之一是患者服药依从性低。就以上发现的意义作了讨论。 相似文献
8.
S. Haruyama H. Mori L. M. Wan Y. Shinozaki H. Sakamoto H. Okino 《Medical & biological engineering & computing》1994,32(Z1):S91-S98
We proposed a mathematical model to describe the early filling process of the left ventricle and applied the model toin vivo experiments. The solution of a second-order differential equation indicated that the pressure difference between the left
atrium and ventricle during ventricular filling (PD) could be explained by a transient response, i.e. decremental oscillation,
in an LCR circuit. Thereafter, we analysed the sequence of PD during vagal stimulation with two catheter-tip manometers in
12 anaesthetised dogs and evaluated changes in the parameters of the system under various haemodynamic conditions. The values
of ωn and ξ were quite stable among beats within an episode of vagal stimulation, between episodes and even among dogs, despite
the changes in haemodynamic variables. Pericardiotomy and partial discommunication of the mitral valve with the left ventricular
free wall by cutting the mitral chordal tendons decreased ωn and increased ζ, mainly because of the increase in CLV. Occlusion of the coronary vascular beds with large numbers of microspheres increased ωn and decreased ζ, mainly because of the decrease in CLV. Mitral obstruction with an inflated balloon (increase in R) abolished the oscillatory changes and produced and exponential
decay sequence of PD. In conclusion, both the logical and experimental approaches indicated that the sequence of PD could
be considered as decremental oscillation in the LCR circuit and the parameters ωn and ξ could be good indices of the diastolic property of the left ventricle 相似文献
9.
采用成年狗正常股动脉段6例,测定其拉伸后的压力一容积关系,并求出其顺应性。另取狗股狗股动脉段30例拉伸固定后,观测其形态结构变化。发现狗股动脉段拉伸后的P-V曲线可用抛物线来拟合,狗股动脉段拉伸15%后顺应性明显下降,其形态结构无明显改变,拉伸30%后才出现明显的结构改变。狗股动脉拉伸后顺应性变化的出现较形态结构变化早。 相似文献
10.
研究轴向应变对血管顺应性的影响 ,明确能否通过调节吻合张力建立顺应性一致的静脉移植修复动脉缺损模型。取一段做完轴向拉伸实验的血管 (兔股动、静脉分别为 13、12条 ) ,测量不同伸长率下的压力—容积曲线 ,换算为压力—标准容积曲线 ,用幂函数 P=M1 × [еM2 ( v- v0 ) - 1]进行拟合 ,用多项式 M=a1 λ5+a2 λ4 +a3λ3+aλ2 +a5λ+a6 拟合 M- λ数据。由 P=M1 × [еM2 ( v- v0 ) - 1]得出在动脉平均压 (11.78KPa)下血管顺应性 dv/ dp=1/ (M1 ×M2 +11.78M2 )。由张力 T与伸长率 λ的单值对应关系建立起 T与顺应性 dv/ dp的单值对应关系 ,发现在张力 1.19g时 ,在动脉平均压下 ,动静脉的顺应性一致 ,为 0 .0 31,其所对应的动静脉伸长率为 :1.6 7及 1.32 相似文献